BODY SYSTEMS

BELL RINGER What system sends messages in the

form of electrical signals?

CH 37 BODY ORGANIZATION Objectives:

Identify levels of structural organization within the human body

Analyze four kinds of body tissue List the bodies major organs Evaluate the importance of endothermy

in maintaining homeostasis.

ORGANIZATION Four levels of organization

Cells Tissues Organs

Organ Systems

TISSUE Tissue-group of cells that work together

to perform a specific function.

4 Types of Tissues Epithelial

Connective Nervous Muscle

TISSUE Epithelial-lines most body surfaces and

protects other tissue from damage and dehydration.

Nervous-consists of nerve cells and carry information throughout the body.

Connective-support, protect, and insulate the body

Muscle-enables the movement of body structure by muscle conratcion.

Example: The function of the spongy tissue in the lung is to take in oxygen and release carbon dioxide.

ORGAN Organ-collection of tissues that carry on

a specialized function in the body.

Example: the function of the lung is to take oxygen from the air and deliver it to the blood and take carbon dioxide from the blood and deliver it to the air.

STEM CELLS

STEM CELLS Undifferentiated cells that give rise to all

of the cell types in the body.

Immortal and divide indefinitely

Stem cells come from embryos

Why is stem cell research controversial?

ORGAN SYSTEM A group of organs that work together to

carry out major activities or processes

ORGAN SYSTEMS

BODY CAVITIES Human body contains four large fluid

filled spaces to house organs Thoracic Cranial

Abdominal Spinal

BODY CAVITIES